1. Field of the Invention
This invention particularly relates to poisonous lures for eradication of the common phylum-mollusca (snail and slug) garden pests; and more specifically, the invention relates to those temporary devices which are manually positioned partially into the ground via a downward spike like member.
2. Description of the Prior Art
Heretofore, as revealed via prior art patent-search, it has generally been the practice of inventive thinking to produce poisonous-lures for snails defining a housing structure in which the snail actually enters, and within which the snail even dies, once having partaken of the fatal lure substance. A well known exception to such structural configuration has been in the form of a stake-like poisonous-lure for ant-insects, which was set forth in U.S. Pat. No. 2,547,314 (filed Aug. 1, 1944). This shows a vertical light-weight corrugated-metal stake portion, to one side-surface of which is tab-crimped a small circular container filled with a gelatinous substance deadly to ants. The object of this construction was found in the particular undulations which provided tiny pocket areas attractive to the ants, arranged about the perimeter of the poison container, in addition to a central entry-hold of about 5/16"-diameter. These devices are still a popular selling ant-lure, but are not known to be effective against snails in that they do not afford an attractive cool crevice in which to dwell.
The oldest known device known to employ a spike for retention into the ground is that of U.S. Pat. No. 1,729,389 (filed April 1928), comprising a poison container-cup having an underside spike, and a lift-off cap thereupon; allowing filling of the poison into the cup. Still other inventions more specific to snail control are known, for example old U.S. Pat. No. 1,872,780 (filed November 1920) shows a dish-like base over which is positioned a special cover portion having several entryway arches. Another example of a spiked type of snail lure is found in U.S. Pat. No. 2,239,937 (filed January 1939). Which is a three-piece apparatus called a "bait protector," wherein a long rod-like spike with a loop on it's uppermost end, is equipped with an annular hood and is inserted down through the center of a bait-dish and down into the ground. This apparatus would thus be too bulky to use in many desired applications, where a dish and overhanging hood could not fit, such as in a flower-pot.
Later, U.S. Pat. No. 2,837,861 (filed July 1957) introduced a spiked insecticide-container having an integral annular tray and a dome-like top having many tiny holes for entry of ants. Again the annular shape would tend to be rather bulky. And U.S. Pat. No. 3,427,743 (filed January 1969) introduced another spike type insect bait-dispenser with an annularly-compartmented tray, but which uppermost hood member fits down to the ground, while an uppermost installation T-handle is unscrewable from the central spike so as to prevent the installed device from being readily accessed by children and pets. Again though, this configuration is too bulky for use in flower-pots for example.
Then U.S. Pat. No. 3,772,820 (filed November 1973) featured central ground-spike with an annular dome-like hood having a scalloped-rim portion positioned upon the ground, thereby enabling snails and slugs to enter the hood overlaying confines. A vertically adjustable portion of the hood may be raised to allow more water to enter from some lawn-sprinkler, thereby metering water therein to activate the poison-bait. Again, the device is too bulky in diameter. U.S. Pat. No. 3,978,607 (filed September 1976) again featured a bait-dish located beneath a perimeter-scalloped hood member, with a central spike passing down unitingly through the aggregate members and into the ground;--including a convenient grasping member, enabling the device to be easily withdrawn from the ground for relocation. But again, the device is too bulky for flower-pot use.
Next, U.S. Pat. No. 4,485,582 (filed December 1984) shows an insect lethal-feeding station, rather mushroom like in formation; including a tubular ground-spike member for thrusting into the earth. The spike is formed integrally with an upper tray-like bait holding portion, which is topped with a transparent-cap having three perimeter entry apertures. Thus, while the device could be installed in a flower-pot, it's structural provisions appear to accommodate use for bugs and ants only.
Further, U.S. Pat. No. 4,821,452 (filed December 1987) shows a one-piece dome shaped snail-lure, the perimeter of which features three snail entry arches, the sides of which extend downward in a V-shaped manner so that the dome may be easily stabilized an inch or two into the ground by these three prongs. Once having entered the shady confines of the dome, the snail is enticed to climb the inside wall surface between the arches, so as to access the lure of a poison-bait gel-substance applied to the ceiling of the dome chamber. While, the poison is protected from sprinkling water, and not accessible to child or pet while the device is implanted, it is again too bulky to be installed into a flower-pot. Thus, one can see from this most relevant known invention-art, that there is still room for improvement in devising a ground snails, yet readily installed into a flower-pot.
Finally, British Patent #1,448,214 (filed Dec. 14, 1972) discloses a garden pest eradicator device essentially comprised of a rectangulary shaped, closed canopy mounted upon a vertical stake. However, the narrow vertical stake disclosed in the British '214 patent is not particularly suitable or attractive as a climbing surface for snails and slugs. Additionally, the configuration of the '214 patent is particularly bulky which would effectively prevent its use in enclosed spaces such as flower pots and the like. Further, the eradicator device shown in the British '214 patent also does not permit easy installation or replacement of bait. Specifically, the user of the British '214 patent must use a spatula-like tool to apply bait to the underside of the closed canopy.
The foregoing discussion of prior art garden pest control devices, reveals that there is a need for a compact snail and slug eradication device which can be readily installed into a flower bed or flower pot. There is also a need in the prior art for such a snail or slug eradication device which can be inexpensively made using known techniques such as plastic extrusion. Further, there is also a need in the prior art for a snail and slug eradication device which allows easy access for replacement of the poison bait. Such access permits the user to maximize the effectiveness of the eradication device by periodically supplying it with fresh bait.
Additionally, one of the more commonly available baits is purchased in a liquid form and, when applied to a surface, it then dries to either a semi-viscous or solid form prior to being consumed by the snails and slugs. Typically, when liquid bait is applied, the device cannot be used until the bait dries as otherwise the bait would simply run off of the device. Further, if liquid bait is applied to a smooth surface, it may fail to adhere to the surface after it has dried. Hence, a need also exists in the prior art for a snail and slug eradication device which provides both ready access to the bait chamber as well as providing a surface to which liquid bait will readily adhere.